直接跟学校申请就可以吗？怎么才能拿到i-20呢？
-You need to apply for a study program in a school, and the school will issue I-20 to you if they approve your application for study. Then, you can file I-539 to USCIS for change of status from L-2 to F-1. Talk to the school International Office, and they will tell you how to do it.
